https://scholars.lib.ntu.edu.tw/handle/123456789/414376
標題: | High-resolution crystal structure of a truncated ColE7 translocation domain: Implications for colicin transport across membranes | 作者: | Cheng Y.-S. Shi Z. Doudeva L.G. Yang W.-Z. Chak K.-F. Yuan H.S. |
關鍵字: | Colicin structure;Colicin translocation domain;Crystal structure;Membrane translocation;Protein cellular import | 公開日期: | 2006 | 卷: | 356 | 期: | 1 | 起(迄)頁: | 22-31 | 來源出版物: | Journal of Molecular Biology | 摘要: | ColE7 is a nuclease-type colicin released from Escherichia coli to kill sensitive bacterial cells by degrading the nucleic acid molecules in their cytoplasm. ColE7 is classified as one of the group A colicins, since the N-terminal translocation domain (T-domain) of the nuclease-type colicins interact with specific membrane-bound or periplasmic Tol proteins during protein import. Here, we show that if the N-terminal tail of ColE7 is deleted, ColE7 (residues 63-576) loses its bactericidal activity against E. coli. Moreover, TolB protein interacts directly with the T-domain of ColE7 (residues 1-316), but not with the N-terminal deleted T-domain (residues 60-316), as detected by co-immunoprecipitation experiments, confirming that the N-terminal tail is required for ColE7 interactions with TolB. The crystal structure of the N-terminal tail deleted ColE7 T-domain was determined by the multi-wavelength anomalous dispersion method at a resolution of 1.7 ?. The structure of the ColE7 T-domain superimposes well with the T-domain of ColE3 and TR-domain of ColB, a group A Tol-dependent colicin and a group B TonB-dependent colicin, respectively. The structural resemblance of group A and B colicins implies that the two groups of colicins may share a mechanistic connection during cellular import. ? 2005 Elsevier Ltd. All rights reserved. |
URI: | https://scholars.lib.ntu.edu.tw/handle/123456789/414376 | ISSN: | 00222836 | DOI: | 10.1016/j.jmb.2005.11.056 |
顯示於: | 植物科學研究所 |
在 IR 系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。